console.log('Hello,TypeScript!');
let message: string = 'He llo,Ty peSc rip t!';
console.log(message);
console.log(message.length);
let numbers: number[] = [1, 2, 3, 4, 5];
let strings: string[] = ['Hello', 'World'];
console.log(strings);
 let strings1=message.split(' ');
let mixed: (number | string)[] = [1, 'Hello', 2, 'World'];
type CustomArray = (number | string)[]; //类型别名
let customArray: CustomArray = [3, 'Hello', 4, 'World'];
console.log(customArray);
console.log(strings1);
console.log(mixed);
console.log(numbers);
numbers.forEach((num) => {
    numbers.push(num * 2);
})
console.log(numbers);
let person: { name: string; age: number } = { name: 'John', age: 30 };
console.log(person);